Cationic lipid-mediated enhancement of nucleic acid immunization of cats

Abstract

The present invention relates to a method to introduce a nucleic acid molecule into a felid by administration of a nucleic acid-cationic lipid complex composition. The method includes the step of administering to the felid, by a parenteral route, a nucleic acid-cationic lipid complex to elicit and/or enhance an immune response. In one embodiment, this method enhances the immune response in a felid compared to a method in which a naked DNA vaccine is administered to a felid. Also provided is a method to deliver a nucleic acid to a felid. This method comprises parenterally administering to the felid a composition that includes a nucleic acid molecule complexed with a cationic lipid.

1. A method to elicit an immune response to a feline leukemia virus antigen in a felid, said method comprising parenterally administering to said felid a composition comprising a nucleic acid molecule complexed with a cationic lipid, wherein said nucleic acid molecule encodes said antigen. 
     
     
       2. The method of  claim 1 , wherein said immune response comprises an antibody response. 
     
     
       3. The method of  claim 1 , wherein said immune response comprises a cell-mediated response. 
     
     
       4. The method of  claim 1 , wherein said immune response protects said felid from disease. 
     
     
       5. The method of  claim 1 , wherein said cationic lipid comprises a tetramethyltetraalkyl spermine analog lipid. 
     
     
       6. The method of  claim 1 , wherein said felid is selected from the group consisting of domestic cats, wild cats, and zoo cats. 
     
     
       7. The method of  claim 1 , wherein the felid is selected from the group consisting of domestic cats, lions, tigers, leopards, panthers, cougars, bobcats, lynx, bobcats, lynx, jaguars, cheetahs, and servals. 
     
     
       8. The method of  claim 1 , wherein the felid is a domestic cat. 
     
     
       9. A method to produce enhanced expression of a nucleic acid molecule in a felid comprising
 obtaining an isolated nucleic acid molecule, wherein said isolated nucleic acid molecule comprises an operative regulatory sequence linked to a nucleic acid sequence encoding a feline leukemia virus protein; 
 complexing said isolated nucleic acid molecule with a cationic lipid; and 
 parenterally administering said lipid-complexed nucleic acid molecule to a felid. 
 
     
     
       10. The method of  claim 9 , wherein said method results in enhanced expression of said feline leukemia virus protein. 
     
     
       11. The method of  claim 10 , wherein said leukemia virus protein is an antigen. 
     
     
       12. The method of  claim 9 , wherein said cationic lipid comprises a tetramethyltetraalkyl spermine analog lipid. 
     
     
       13. The method of  claim 9 , wherein said step of administering is selected from the group of intramuscular administration, intravenous administration, subcutaneous administration, intradermal administration, and intraperitoneal administration. 
     
     
       14. The method of  claim 9 , wherein said felid is selected from the group consisting of domestic cats, wild cats, and zoo cats. 
     
     
       15. The method of  claim 9 , wherein the felid is selected from the group consisting of domestic cats, lions, tigers, leopards, panthers, cougars, bobcats, lynx, bobcats, lynx, jaguars, cheetahs, and servals. 
     
     
       16. The method of  claim 9 , wherein the felid is a domestic cat.